F.lux and memory usage

Hello !
I have a very annoying issue with F.lux and I need help.
Each time F.lux start to change screen colors (the evening and the morning), my computer starts to be very slow and the swap memory enlarges nonstop. I just got a message telling me to close apps to free memory space ! ...
It always happens at the same hour, defined in f.lux properties.
This doesn't happen if f.lux process is not running.
You can see on the pictures that the swap files inflates when f.lux is doing the transition.

I don't want to reboot each time F.lux finishes to do the transition !
:confused: